tree 513c93350c01b4f42e071edd7f5bcc7eacf881b3
parent 79362e3307a52b69014fb4930b7fa0395caaa59f
author James Zern <jzern@google.com> 1491363437 -0700
committer James Zern <jzern@google.com> 1493408703 +0000

Resolve -Wshorten-64-to-32 in highbd variance.

For 8-bit the subtrahend is small enough to fit into uint32_t.

cherry-picked from libvpx:
47b9a0912 Resolve -Wshorten-64-to-32 in highbd variance.

This is the same that was done for:
c0241664a Resolve -Wshorten-64-to-32 in variance.

For 10/12-bit apply:
63a37d16f Prevent negative variance

BUG=aomedia:445

Change-Id: Iab35e3f3f269035e17c711bd6cc01272c3137e1d